上腺素是正常的心血管应对压力所需的,在甲胺N-甲基转移酶淘汰赛小鼠中
Xuping Bao1, Chuanyi M Lu, Fujun Liu
1Department of Medicine, University of California San Diego, USA. xbao@ucsd.edu
Circulation
|August 19, 2007
概括
在压力期间,上腺素对于正常的血压和心脏填充至关重要,但对于休息的心血管功能或在压力期间心率增加至关重要. 这项研究使用了小鼠模型来研究上腺素的作用.
科学领域:
- 心血管生理学心血管生理学
- 内分泌学 在内分泌学.
- 神经科学是一个神经科学.
背景情况:
- 上腺素 (EPI) 是一种关键的神经递质和激素.
- 它在休息和压力期间对心血管调节的精确作用仍然不完全理解.
研究的目的:
- 调查上腺素在休息和生理压力期间心血管调节中的作用.
- 阐明上腺素在血压,心率和心脏输出调节中的特定功能.
主要方法:
- 通过敲除乙醇胺N-甲基转移酶 (PNMT) 基因,生成了缺乏上腺素的小鼠模型.
- 通过远程测量在休息和运动期间监测心血管参数 (血压,心率).
- 在各种生理条件下使用心声回声学评估心脏结构和功能.
主要成果:
- 缺乏上腺素的小鼠表现出正常的休息心血管功能和上腺素水平.
- 在昏倒的小鼠中,在交感抑制和炼期间观察到血管扩张障碍.
- 心脏重塑,特别是增加左心室后壁厚度,在没有变大的情况下被观察到.
- 由于末端透缩体积的减少,心脏输出量减少发生在清醒,压力突击小鼠中.
结论:
- 在压力期间,上腺素对于维持正常血压和心脏填充反应至关重要.
- 上腺素不需要用于应对压力的心率反应 (心跳动).
- 静止时的正常心血管功能似乎不依赖于上腺素.
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